 /*******************************************************************************
  * Copyright (c) 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  ******************************************************************************/

 package org.eclipse.ui.ide.undo;

 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IFolder;
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.ui.internal.ide.undo.FileDescription;
 import org.eclipse.ui.internal.ide.undo.FolderDescription;
 import org.eclipse.ui.internal.ide.undo.ProjectDescription;

 /**
  * ResourceDescription is a lightweight description that describes the common
  * attributes of a resource to be created.
  *
  * This class is not intended to be extended by clients.
  *
  * @since 3.3
  *
  */
 public abstract class ResourceDescription {

     /**
      * Create a resource description given the specified resource. The resource
      * is assumed to exist.
      *
      * @param resource
      * the resource from which a description should be created
      * @return the resource description
      */
     public static ResourceDescription fromResource(IResource resource) {
         if (resource.getType() == IResource.PROJECT) {
             return new ProjectDescription((IProject) resource);
         } else if (resource.getType() == IResource.FOLDER) {
             return new FolderDescription((IFolder) resource);
         } else if (resource.getType() == IResource.FILE) {
             return new FileDescription((IFile) resource);
         } else {
             throw new IllegalArgumentException ();
         }
     }
     
     /**
      * Create a resource handle that can be used to create a resource from this
      * resource description. This handle can be used to create the actual
      * resource, or to describe the creation to a resource delta factory.
      *
      * @return the resource handle that can be used to create a resource from
      * this description
      */
     public abstract IResource createResourceHandle();

     /**
      * Get the name of this resource.
      *
      * @return the name of the Resource
      */
     public abstract String getName();
     
     /**
      * Create an existent resource from this resource description.
      *
      * @param monitor
      * the progress monitor to use
      * @return a resource that has the attributes of this resource description
      * @throws CoreException
      */
     public abstract IResource createResource(IProgressMonitor monitor) throws CoreException;
     
     /**
      * Given a resource handle, create an actual resource with the attributes of
      * the receiver resource description.
      *
      * @param resource
      * the resource handle
      * @param monitor
      * the progress monitor to be used when creating the resource
      * @throws CoreException
      */
     public abstract void createExistentResourceFromHandle(IResource resource,
             IProgressMonitor monitor) throws CoreException;
     
     /**
      * Return a boolean indicating whether this resource description has enough
      * information to create a resource.
      *
      * @return <code>true</code> if the resource can be created, and
      * <code>false</code> if it does not have enough information
      */
     public abstract boolean isValid();
     
     /**
      * Record the appropriate state of this resource description using
      * any available resource history.
      *
      * @param resource
      * the resource whose state is to be recorded.
      * @param monitor
      * the progress monitor to be used
      * @throws CoreException
      */
     public abstract void recordStateFromHistory(IResource resource,
             IProgressMonitor monitor) throws CoreException;
     
     /**
      * Return a boolean indicating whether this description represents an
      * existent resource.
      *
      * @param checkMembers
      * Use <code>true</code> if members should also exist in order
      * for this description to be considered existent. A value of
      * <code>false</code> indicates that the existence of members
      * does not matter.
      *
      * @return a boolean indicating whether this description represents an
      * existent resource.
      */
     public abstract boolean verifyExistence(boolean checkMembers);
 }

